Method for the manufacture of thin-walled shaped articles of thermoplastic material
ApplicationNo. 09867434 filed on 05/31/2001
US Classes:264/37.17, Of gas utilized for heating or cooling264/40.1, WITH MEASURING, TESTING, OR INSPECTING264/322, Initially softening workpiece264/544, Starting material is nonhollow planar finite length preform or product is finite length34/619Including horizontal support
ExaminersPrimary: Lee, Edmund H.
Attorney, Agent or Firm
Foreign Patent References
International ClassB29C 51/02
AbstractA sheet of plastic to be thermoformed into an appliance liner is brought to a substantially uniform temperature, preferably to a temperature differential of less than 5° F. throughout, by directing a fluid medium upon opposing side surfaces of the sheet. In the most preferred form of the invention, the fluid medium is constituted by air which is heated, impinged upon the opposing surfaces and recirculated, with the temperature and flow rate of the air being controlled based on sensed operating parameters.